My sets destroyed by the organisation (6)
I believe the answer is:
system
'the organisation' is the definition.
(synonyms)
'my sets destroyed' is the wordplay.
'destroyed' indicates an anagram.
'my'+'sets'='mysets'
'mysets' is an anagram of 'SYSTEM'.
'by' acts as a link.
(Other definitions for system that I've seen before include "Method of organization" , "Method (of betters?)" , "Method of organisation" , "Organisational method" , "Group of elements working as a whole" .)